Hospital beds and stretchers typically have an upper body support section which can be pivoted by a drive mechanism from a horizontal position to an inclined position in order to raise the patient to a partially sitting position or a substantially fully sitting position. Often, these beds also have a knee support section which can be pivoted between horizontal and inclined positions so that, when the patient is raised to the sitting position, the patient does not tend to slide toward the foot of the bed.
When an emergency occurs while the patient is in the sitting position, for example where the patient experiences heart failure, it is important that the patient be moved as rapidly as possible back to the horizontal position so that appropriate therapy such as CPR (cardiopulmonary resuscitation) can be administered. The manual or motor-driven mechanism typically utilized to raise and lower the upper body support section or knee support section tends to move the section far too slow to be satisfactory for use in an emergency situation. Therefore, emergency releases have previously been developed to permit the upper body support section to be quickly disengaged from the drive mechanism for rapid movement to the horizontal position.
While the prior arrangements have been generally adequate for their intended purposes, they have not been satisfactory in all respects. For example, some are relatively complex and expensive, whereas others use hydraulic fluid which may be subject to leakage and the attendant risk of slippery spots on hospital floors.
Accordingly, it is an object of the present invention to provide an improved arrangement for rapidly disengaging an upper body support section of a bed from its drive arrangement.
A further object of the invention is to provide such an arrangement which is entirely mechanical, and is of relatively simple and inexpensive construction.
A further object is to provide such an arrangement which is reliable and has a relatively long operational lifetime, and requires little or no maintenance.
A further object is to provide such an arrangement in which a single manually operable release handle can release both the upper body support section and the knee support section, and in which the manual release can be easily and conveniently effected from either side of the bed.